Heats of dilution of aqueous electrolytes. Temperature dependence

Abstract

The heats of dilution of KCI, MgCI2, Na2S04, and MgS04 were measured over a concentration range of 0.005-2.Om at temperatures between 40-80°C. The data were extrapolated to infinite dilution by use of the Debye-Hückel limiting law to obtain relative apparent molal heat contents ( _). The heats of dilution of MgCI2 and MgS04 were measured at 25 °C and combined with the low concentration work of Lange and Streeck to yield values of <f>L. The relative partial molal heat content of solvent and solute was calculated from the experimental values. The heat content data were then used to calculate activity and osmotic coefficients in the temperature range 40-80°C.

Isopiestic determination of the osmotic and activity coefficients of (magnesium chloride + water) and (lithium chloride + magnesium chloride + water) atT=313.15K

“…Both results, ours and the reference, are in good agreement over the whole range of concentration •, results by Snipes et al (4) considered in this work. The experimental osmotic coefficients of magnesium chloride were fitted by the Hamer and Wu (5) equation:…”

“…In figure 1, the experimental osmotic coefficients of magnesium chloride, obtained in this study, together with those reported by Snipes et al (4) are shown for comparison. Both results, ours and the reference, are in good agreement over the whole range of concentration •, results by Snipes et al (4) considered in this work.…”

Dissolution enthalpy of anhydrous sodium sulfate in water. Experimental measurements and treatment with the electrolyte-NRTL model

“…Dilution enthalpies have been reported close to room temperature by Wallace and Robinson, (10) Thompson et al, (11) Leung and Millero, (12) and to T = 472.95 K by Mayrath and Wood. (13) Snipes et al (14) reported apparent relative molar enthalpies at the intermediate temperatures 313.15 K, 335.25 K, and 355.15 K, but their values were obtained by fitting experimental results of the enthalpy of dilution.…”

Thermodynamic Phase And Chemical Equilibrium At 0-110 C For The H+-K+-Na+-Cl--H2O System Up To 16 Molal And The HNO3-H2O System Up To 20 Molal Using An Association-Based Pitzer Model Compatible With ASPEN Plus

“…[10]) were regressed from the temperature-dependent correlation given by Greenberg & Moller (1989) for 0-250û C and I ≤ 18 m. The correlations of Greenberg & Moller (1989) were assessed by comparing predictions with the following activity/osmotic coefficient data for the KCl-H 2 O system: Robinson & Stokes (1959) and Hamer & Wu (1972) at 25û C, Harned & Owen (1958, pg. 727) at 0-40û C, Hellams et al (1965) at 45û C, Humphries et al (1968) at 60û C, Moore et al (1972) and the data of Snipes et al (1975; as given by Zemaitis et al, 1986, pg. 138) at 80û C, and Holmes et al (1978) at 109û C. There was good agreement.…”